Robert Arthur Talbot Gascoyne-Cecil, 3rd Marquess of Salisbury, KG, GCVO, PC (3 February 1830 - 22 August 1903), known as Lord Robert Cecil before 1865 and as Viscount Cranborne from 1865 until 1868, was a British statesman and thrice Prime Minister, serving for a total of over 13 years. He was the first British Prime Minister of the 20th century and the last Prime Minister to head his full administration from the House of Lords